diff --git a/arch/sim/src/sim/sim_oneshot.c b/arch/sim/src/sim/sim_oneshot.c
index d9983571d6..68a46ee0dd 100644
--- a/arch/sim/src/sim/sim_oneshot.c
+++ b/arch/sim/src/sim/sim_oneshot.c
@@ -437,6 +437,7 @@ void up_timer_initialize(void)
 
 void sim_timer_update(void)
 {
+#ifdef CONFIG_SIM_WALLTIME_SLEEP
   static uint64_t until;
 
   /* Wait a bit so that the timing is close to the correct rate. */
@@ -444,7 +445,6 @@ void sim_timer_update(void)
   until += NSEC_PER_TICK;
   host_sleepuntil(until);
 
-#ifdef CONFIG_SIM_WALLTIME_SLEEP
   sim_timer_update_internal();
 #endif
 }